Brake mechanism.



No. 866,328. PATENTED SEPT. 17, 1907. A. P. BRUSH.

BRAKE MECHANISM.

, APPLICATION FILED AUG.31,1906.

MTNEEEEE- W? wwm fiwzm a UNITED STATES ALANSON P." BRUSH, OF' DETROIT, MICHIGAN.

BRAKE mrcnamsu.

Specification of Letters Patent.-

Patented Sept. 17, 1907.

Applioation filad August 31, 1906; Serial No. 332;781,

To all whom. it may concern: p

Be it known that I, ALANSON P. Bnusn, a citizen of the United States, residing at Detroit, county of Wayne, State of Michigan, have invented a certain new and useful Improvement in Brake Mechanisms: of which the following is a specification, reference being had to the accompanying drawings, which form a part of this specification.

My inventionis designed to provide an improved brake mechanism, the same being more particularlydesigned for use in automobiles and like structures, but I do not limit myselfthereto, as my invention contemplates as coming within its scope, any use to which it may be applied. j

My invention consists of the structure her inafter described and claimed, and illustrated in the accompanying drawings, in which,

Figure 1 is a view in elevation illustrating features of my invention showing the mechanism in released position. Fig. 2 is a view in transverse section. Fig. 3 is a similar view to Fig. 1, but showing the mechanism set with the rotation of the drum in the direction indicated by the arrow. Fig. 4 is a detail view illustrating the construction of the wedge.

My improved brake mechanism applies to that class of bral tes wherein an internal friction drum is provided with an internal friction band. Accordingly a represents the drum, which may be as shown herewith, a combined brake drum and sprocket wheel, and b is the internal friction band. The extremities of, the band are preferably provided with angularly and diverging .wedge shaped surfacesindicated at c and d. Between the extremities of the friction band is located a fixed stop indicated at e. Means are also provided to force the extremities of the band apart, and against the drum. The means shown herewith consists essentially of a wedge f provided with are shaped faces indicated at g, g to contact with the wedge shaped faces c, d of the band, said wedge being pivoted upon and actuated by a lever h fulcrumed as at 'i upon a stationary part of the axle, the wedge being preferably pivoted on a pin indicated at 3' rigidly engaged with the lever and upon which the wedge is sleeved. The fixed stop is also shown projecting from a fixed part of the axle. The shaft or spindle upon which the drum is mounted is indicated at It. When the brake isset by the movement of the lethe fixed step e, the wedge f being thus shifted in itsposition so as to throw the larger amount of pressure upon the other end of the band. It will .be obvious that unanis'm overthat which may be caused by the pressure of the wedge alone. i It will be apparent that the action of the brake band is practically that of a. conventional single acting hand brake mechanism with the superiority of operating equally well in either direction. Furthermore, since the wear of the friction surfaces will furtherincreasethe displacement of the position of the wedge the pressure applied on the movable end of the band, the wearing of the brake surfacesincreases the efficiency of the mechanism. It will be obvious that when the drum rotates, .fo example, in the direction shown by the arrow in Figs. 1 and 3, and the ends of the band are forced apart and against the drum, the extremity c of the brake band will be drawn toward the stop e. v The rotation of the drum will obviously, by its frictional contact with the brake band, tend to draw the extremity c of the brake band toward the stop. When the rotation of the drum is reversed, however, the reverse effect will obviously result, the extremity d of the brake band being drawn by frictional contact with the drum toward the fixed stop so that it will be seen that the brake will work equally the same in which ever direction the drum may be rotated. It will also be observed that a very short movement of the lever ,will set the brake. It is clear'that by the setting of the brake, by the advancement of the wedge, any wear upon the wearing faces of the mechanism will be taken up, any wear simply necessitating a corresponding advance in the movement of the lever.

An'important featpre of the invention lies in the fact that the movement of the drum assists in setting the brake. Another important feature of the invention also lies in the fact that the brake will act just as Well in one direction as in the other, so that while I employee. single acting brake band, I practically have a double acting brake. The band, when released, is supported upon arms 1 projecting from the stationary part moi the axle. The brake band is simply swung in place without being attached to any other part of the mechanism. 7

A brake so constructed is obviously economical as well as of superior efficiency, while the frictional contact of the drum with the brake band, in either direction, exerts a corresponding frictional tension upon the band. The lever will thus cause a wedging effect upon the brake band irrespective of the relative movements of the band and drum.

While I have shown a fixed stop between the .ex

1 stop betweenthe'endsof the band, and means to be forced 'tremities of the band, I do not myself solely to locating the stop between the extremities of the band, as any suitable means may belpm'vided to limit the rotation of the 'band in either direction. The lever may be iulcrume i upon anyfiied; part of, the mechanism also, within the scope of my invention.

I What I claimas my invention is:

1. A brake mechanism comprising a rotatable brake drum, an unattachedfrictioh band within the drum having both extremities formed with wedge shaped faces, a fixed between the ends of the band to'force the hand against the drum, whereby the brakeiwiil be set in either. direction.

2.. A brake mechanism comprising a rotatable drum,an unattached expansible band within the drum normally free to rotate with the drum, a stop to limit the rotation of the band with the drum, and means to be forced between the extremities drum. I v 8. A band? brake mechanism comprising a rotatable brake drum, an unattached 'expansibie friction band within the of theband to expand the band within the" drum, and means to expand said band whereby the 'rota tion of the drum in either direction canses a part of the frictional tension; 1 I j 4; A bandbra l revinecha nism comprising a friction drum, an unattached friction band within the drum having a limited movement with the drum in either direction, means shaped faces at 'the extremities thereof, means to limit therotation of the band, a wedge shaped device to be forced between the ends of the-band provided with means toa'ctnate the wedge.

' In" esti rnony whereof I have signed this specification.

in the presence of two subscribing witnesses.

v' e 7' ALANsoN P. BRUSH. Witnesses. a

N; S. WRIGHT, 

